package org.bouncycastle.asn1.x509;

import org.bouncycastle.asn1.ASN1Encodable;
import org.bouncycastle.asn1.ASN1EncodableVector;
import org.bouncycastle.asn1.ASN1Sequence;
import org.bouncycastle.asn1.DERObject;
import org.bouncycastle.asn1.DERSequence;

/**
 * <code>UserNotice</code> class, used in <code>CertificatePolicies</code> X509 extensions (in policy qualifiers).
 * 
 * <pre>
 * UserNotice ::= SEQUENCE {
 *      noticeRef        NoticeReference OPTIONAL,
 *      explicitText     DisplayText OPTIONAL}
 * 
 * </pre>
 * 
 * @see PolicyQualifierId
 * @see PolicyInformation
 */
public class UserNotice extends ASN1Encodable {
    private NoticeReference noticeRef;
    private DisplayText explicitText;

    /**
     * Creates a new <code>UserNotice</code> instance.
     * 
     * @param noticeRef
     *            a <code>NoticeReference</code> value
     * @param explicitText
     *            a <code>DisplayText</code> value
     */
    public UserNotice(NoticeReference noticeRef, DisplayText explicitText) {
        this.noticeRef = noticeRef;
        this.explicitText = explicitText;
    }

    /**
     * Creates a new <code>UserNotice</code> instance.
     * 
     * @param noticeRef
     *            a <code>NoticeReference</code> value
     * @param str
     *            the explicitText field as a String.
     */
    public UserNotice(NoticeReference noticeRef, String str) {
        this.noticeRef = noticeRef;
        this.explicitText = new DisplayText(str);
    }

    /**
     * Creates a new <code>UserNotice</code> instance.
     * <p>
     * Useful from reconstructing a <code>UserNotice</code> instance from its encodable/encoded form.
     * 
     * @param as
     *            an <code>ASN1Sequence</code> value obtained from either calling @{link toASN1Object()} for a <code>UserNotice</code> instance or
     *            from parsing it from a DER-encoded stream.
     */
    public UserNotice(ASN1Sequence as) {
        if (as.size() == 2) {
            noticeRef = NoticeReference.getInstance(as.getObjectAt(0));
            explicitText = DisplayText.getInstance(as.getObjectAt(1));
        } else if (as.size() == 1) {
            if (as.getObjectAt(0).getDERObject() instanceof ASN1Sequence) {
                noticeRef = NoticeReference.getInstance(as.getObjectAt(0));
            } else {
                explicitText = DisplayText.getInstance(as.getObjectAt(0));
            }
        } else {
            throw new IllegalArgumentException("Bad sequence size: " + as.size());
        }
    }

    public NoticeReference getNoticeRef() {
        return noticeRef;
    }

    public DisplayText getExplicitText() {
        return explicitText;
    }

    public DERObject toASN1Object() {
        ASN1EncodableVector av = new ASN1EncodableVector();

        if (noticeRef != null) {
            av.add(noticeRef);
        }

        if (explicitText != null) {
            av.add(explicitText);
        }

        return new DERSequence(av);
    }
}
